Morphology of planktonic zoeal stages of Palicus caronii (Decapoda, Brachyura), identified by DNA barcoding, provides novelties to Palicoidea larval systematics.

The zoeal development of the brachyuran crab, Palicus caronii, comprises two zoeal stages and the morphology is described and illustrated in detail. The zoeae were collected in plankton samples from the Southern Ligurian Sea (Western Mediterranean). Although the morphology of the larval stages of this species was unknown, a combination of characters allowed the zoeae to initially be assigned to the Palicidae, based on the previous unique known first zoeal description of one species of this family. Later, the identification of the larvae as Palicus caronii was confirmed through molecular analysis. The morphological features of the zoeae that characterize the Palicidae and separate them from the Crossotonotidae are confirmed. Also, the larval development comprising only two zoeal stages observed in Palicus caronii, the peculiar and uncommon carapace surface setation, and the presence of anterodorsal and posterodorsal sensory dorsal organs suggest that these characters could be common to the Palicoidea.

Trace elements, rare earth elements and inorganic arsenic in seaweeds from Giglio Island (Thyrrenian Sea) after the Costa Concordia shipwreck and removal.

The occurrence of trace elements, REE and iAs was investigated in macroalgae collected from Giglio Island (Grosseto, Italy), 3 years after the Costa Concordia shipwreck recovery operations. There was a high variability of metals and REE between species, even those belonging to the same phylum. Arsenic level was found within the range of the Tuscany marine environment; the inorganic fraction was from 9% to 31%. Al, Be, Pb and Zn levels in seaweeds from Giglio Island were found to be significantly higher than in macroalgae from other islands of the Tuscany archipelago. REE were double the values found in the Tuscan islands of Elba and Capraia. We suggest that concentrations of metals and REE were influenced by the 3-year-long naval operations carried out for the Costa Concordia shipwreck rescue, and that macroalgae could be suitable bioindicators of perturbations in metal concentrations in the marine environment. CAPSULE: Inorganic contaminants in seaweeds for Giglio Island.

Microalgae treatment removes nutrients and reduces ecotoxicity of diluted piggery digestate.

Liquid digestate is considered as an important by-product of anaerobic digestion of agriculture wastes. Currently, it is very often directly spread on local agricultural land. Yet recently concerns on its environmental risk of this processing has begun to rise. On the other hand, investigations on the effectiveness of microalgae for wastewater treatment have started to consider also this complex matrix. In this study, we cultured the green alga Chlorella vulgaris in diluted digestate coming from the anaerobic digestion of pig slurry and corn, with the aim to significantly reduce its toxicity and its very high nutrient concentration. For this purpose, a battery of toxicity tests composed of four acute and two chronic bioassays was applied after the alga cultivation. Results were compared with those obtained in the initial characterization of the digestate. Results show that highly diluted piggery digestate can be a suitable medium for culturing microalgae, as we obtained a high removal efficiency (>90%) for ammonia, total nitrogen and phosphate, though after a few days phosphorus limitation occurred. Toxicity was significantly reduced for all the organisms tested. Possible solutions for optimizing this approach avoiding high dilution rates are discussed.